In which of the following disorder, the alveoli get filled with fluid leading to severe problems in respiration?

Options

A. Common cold
B. Whooping cough
C. Diphtheria
D. Pneumonia

Explanation

To answer the question regarding which disorder causes the alveoli to fill with fluid, leading to severe problems in respiration, we can analyze each option provided.

### Step-by-Step Solution:

1. **Identify the Disorders**: We have four options to consider:
- Common Cold
- Whooping Cough
- Diphtheria
- Pneumonia

2. **Analyze Common Cold**:
- The common cold, also known as rhinitis, is caused by the rhinovirus.
- It primarily affects the nose and respiratory passages but does not involve the lungs.
- Since it does not affect the lungs, it does not lead to fluid accumulation in the alveoli.
- **Conclusion**: This option is incorrect.

3. **Analyze Whooping Cough**:
- Whooping cough, or pertussis, is caused by the bacterium Bordetella pertussis.
- It is a respiratory disorder but does not directly affect the lungs to the extent of causing fluid accumulation in the alveoli.
- **Conclusion**: This option is also incorrect.

4. **Analyze Diphtheria**:
- Diphtheria is caused by the bacterium Corynebacterium diphtheriae.
- It primarily affects the throat and can cause severe respiratory issues, but it does not lead to fluid filling in the alveoli.
- **Conclusion**: This option is incorrect as well.

5. **Analyze Pneumonia**:
- Pneumonia is caused by various pathogens, including bacteria such as Streptococcus pneumoniae.
- It is characterized by infection in the lungs, leading to inflammation and fluid accumulation in the alveoli.
- This fluid prevents proper gas exchange, resulting in severe respiratory problems.
- **Conclusion**: This option is correct.

### Final Answer:
The disorder in which the alveoli get filled with fluid, leading to severe problems in respiration, is **Pneumonia** (Option 4).

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